The present invention relates to separators for separating a cover sheet from a printing laminate which includes a printing sheet and the cover sheet attached through an adhesive layer to the printing sheet.
Conventionally, tape-like printing laminates which each include a printing sheet or tape of a resin material to which a print ink can easily take well and a cover sheet or tape of paper coated with separating silicon attached through an adhesive layer to the printing sheet or tape are used as printing mediums for tape printers.
Various such printing laminates are prepared which have a width of about 1-5 cm, on which printing tape a character string is printed by a tape printer, and its printed portion is then cut to a predetermined length away from the remaining portion of the tape to form a label. Then, the cover tape is separated from the label and the printed tape portion is then pasted at its exposed adhesive layer to an object.
Since the cover tape has the silicon coating thereon, it is separable from the adhesive layer of the label. However, it is undesirable that the cover tape is easily separated from the printing sheet or tape during handling before printing. Thus, the cover tape is required to be pasted to the adhesive layer with such a pasting force that the cover tape can not be separated easily from the printing tape. Therefore, even when the cover tape is tried to be separated from the label at its corner with fingers, it is considerably difficult to do so well.
In order to facilitate separation of the cover tape from the label, separators have been put to practical use. The separators have a propeller-like rotating body which is rotated by a motor to vehemently hit a corner of the label to thereby give a bending habit to the label at the corner such that the cover tape can be easily separated with fingers from the remainder of the label.
FIG. 11 shows a separator having a simpler structure which has been used actually. FIGS. 12A, B and C show the states of its use. As shown in FIG. 11, the separator 1 has a resin body 2 of a hollow truncated conical shape with a bottom formed at its smaller end and with a slit 3 extending along a ridgeline thereof.
In use, as shown in FIG. 12A, the label 4 is then inserted at one end through the slit 3 into the separator 1 so as to abut on an inner surface 2a of the separator body. The label 4 is then pinched externally at its lower portion 5 near the slit 3 with fingers and slid downward, as shown by an arrow A.
As shown in FIG. 12B, this causes an end of the label 4 to be pressed and rolled up by the tapering hollow inner surface 2a of the separator. Then, the label is pulled upward which allows the rolled-up end of the label 4 to restore its original straightened state with its elasticity. Then, the downward and upward operations of the label 4 in FIGS. 12A and B are repeated. Lastly, when the label 4 is taken out from the separator 1, as shown in FIG. 12C, the label 4 is separated at its end into the printing tape 6 and cover tape 7. Thus, the cover tape 7 can easily be separated with fingers from the printing tape 6.
Each of the method of separating the cover tape by vehemently hitting the corner of the label with the propeller-like rotating body and the method of using the truncated conical-shaped separator 1 of FIG. 11 to separate the cover tape from the remaining printing laminate tape uses a difference in deformation between the printing tape 6 and the cover tape 7. The cover tape 7 has a low elasticity, so that it tends to maintain a bend given by an external force whereas the printing tape 6 has a somewhat higher elasticity because of its resin material to thereby restore its original state easily against its applied bending force.
The outer and inner peripheries of the printing laminate 6 to which a bending force is applied have different radii of curvature, so that each time the printing laminate 6 is bent, the printing laminate 6 and the cover tape 7 are impressed with shearing stresses. This causes the adhering force between the adhesive layer and the cover tape 7 to decrease. Further, a separating force acts between the printing tape 6 and the cover tape 7 due to the difference in their deformations, which leads to separation of the cover tape 7 and the printing tape 6, to which the bending force was applied, from each other at their corner.
The above-mentioned method of vehemently hitting the corner of the label uses an expensive large-scaled propeller-like rotating body. The method of using the truncated conical-shaped separator 1 cannot be easily performed because the label 4 is required to be pinched externally with fingers at its lower portion near the slit 3 in the conical-shaped separator body so as not to be slipped off from the slit while repeating the downward and upward movements of the label 4. Therefore, an unskillful user cannot maintain pinching the lower label portion 5 with fingers close to the slit 3, and cannot cause the label 4 to slide at its end on the inner surface 2a of the separator body and hence the label 4 can not be bent at its corner.
It is therefore an object of the present invention to provide a separator having a simple structure which is capable of easily separating a cover sheet from a printing laminate.
In order to achieve the above object, the present invention provides a separator for separating a cover sheet from a printing laminate which includes a printing sheet and the cover sheet attached separably to the printing sheet, comprising: mouth means through which the printing laminate is inserted; curved means having a curved surface provided deep within the mouth means; and moving means for moving the curved means toward the mouth means to cause the curved means to push at the curved surface a leading end of the inserted printing laminate to thereby curve the printing laminate.
According to the separator, the printing laminate is fixed always appropriately at a position where its cover sheet is separated from its printing sheet, and the printing laminate is thrusted at the leading end by the curving means in a direction reverse to the inserting direction of the printing laminate. Thus, the separator is easy to handle as well as even an unskillful user can surely form a desired bend habit surely at the end of the printing laminate. Separation of the cover sheet from the composite is facilitated.
The separator may further comprise clamping means for clamping the printing laminate at a predetermined position. The separator may also further comprise biasing means for biasing the clamping means toward the predetermined position so as to clamp the printing laminate at the predetermined position.
The moving means may comprise a moving member and an operative member operated for moving the moving member and caracterized in that the moving member moves at about 90 degrees to a direction in which the operative member is operated. The operative member may comprise a sliding surface where the operative member is in contact with the moving member such that a force applied to the operative member is converted by the sliding surface of the operative member to a force applied to the moving member so as to move the moving member toward the leading end of the printing laminate, the force applied to the operative member being at about 90 degrees to the direction of the force applied to the moving member.
The moving member may comprise an operative member and a moving member integral with the operative member, and caracterized in that the operative member and the moving member have the same moving direction.
The moving member may be integral with the curved means. The mouth means may comprise a pair of guides for guiding the printing laminate and disposed at an angle of 30-60 degrees to the direction in which the printing laminate is inserted at the leading end into the mouth means.